The present invention relates to the power steering systems and more specifically to modular electric steering gear subassembly design.
Over the years, power steering has become standard equipment on most vehicles. Most late model passenger cars with power steering use either a power rack and pinion system or an integral power steering gear assembly. Most front wheel drive cars use power rack and pinion systems, while most rear wheel drive systems use an integral power steering gear. Power steering systems are typically either hydraulic-based systems, where fluid pressure is used to aid the steering assembly in turning a vehicle, or electric-based systems, where an electric motor is coupled to the steering assembly to aid the steering assembly in turning the vehicle.
Automobile power steering is actually power-assisted steering. All systems are constructed so that the car can be steered manually when the engine is not running or if the steering system is disconnected from the power source.
One problem common to both hydraulic-based and electric-based power steering systems is that the systems typically must be assembled completely before they can be tested. If a problem in the initial assembly is detected or if the overall system is not functioning properly, the system must be disassembled to determine the root cause of the problem and then be reassembled to test the replaced component. This disassemble/reassemble process is time consuming and costly.
Another problem with typical power steering assemblies is that they are extremely bulky to ship when fully assembled. This bulkiness increases costs associated with packaging efficiency.
Another problem with typical power steering assemblies is commonality. Commonality is highly desirable in automotive assembly plants or other industries, in that individual sub-assemblies may be used on more than one platform. The more commonality among parts, the more efficient the process to make vehicles, and the more cost savings that can be achieved.
It would therefore be desirable to provide a modular power steering assembly that is capable of being tested at various stages prior to final assembly on a vehicle to ensure that various components are functioning properly. It is also desirable that these assemblies are capable of being shipped as subassembly components for efficiency and cost reasons. The modular concept is also highly desirable in that it increases the potential for commonality between vehicle platforms.
The modular design concept has great advantages over typical power steering assemblies. First, it allows the testing and calibration of critical steering gear components independently prior to final assembly.
Next, the modular design concept provides increased packaging flexibility in two ways. First individual sub-assemblies may be shipped independently of other components. Second, shipping costs can be minimized by increasing the usable space in a container by packaging the sub-assemblies prior to final assembly in a more efficient and space conscious manner, not as a bulky final assembly.
Third, the modular design concept can increase component/subassembly commonality across vehicle platforms, which can lead to tremendous cost savings.